Building on models and empirical concepts that were developed last cycle, our broad goal in the proposed project is to use medfly and butterfly model systems in the field to address a series of technical and substantive questions related to aging in the wild, each of which is described within the following four specific aims. Aim 1 is concerned with the ecology of life span in butterflies in Kibale National Park, Uganda and will include tests of hypotheses on suites of traits that are correlated with and contribute to long lifespan using a comparative approach across fruit-feeding butterfly species, and hypotheses concerned with factors determining how wing damage, coloration, egg size, and behavior change with age in butterflies. Aim 2 is concenrred with the ecological analysis using B. anynana and will compare butterfly life history traits in the field and in the laboratory of artificially selected lines of the evolutionary developmental biology (Evo-Devo) model organism Bicyclus anynana and test hypotheses on resource allocation and ecological trade-offs associated with predator defense strategies, using laboratory selected lines of B. anynana. Aim 3 is concerned with the ecology of lifespan in the medfly in Chios, Greece. A 3-year study of aging in wild medflies will be conducted using mass-marking and individual-coding systems to: i) validate (or refute) the assumption that wild-caught flies experience age-specific mortality similar to wild-flies always maintained in the laboratory; and ii) estimate age structure, survival and lifespan in wild populations. A 2- year intensive mark-recapture study of individually-coded medflies will also be conducted to test hypotheses concerning actuarial aging in the wild. Aim 4 will involve statistical models for estimation of survival and age structure in wild populations. Behavioral (e.g. egg laying) data will be used to estimate age structure of wild populations based on egg laying patterns in captured medflies. We will also build on the captive cohort method and expand the concept to include the demography of mark-recapture